You can plot a linear equation, if you are given the coordinates and the slope for THE SAME line.
Assuming you have those, the first step is to find the y-intercept.
That is done by replacing [tex]x[/tex] and [tex]y[/tex] in the general formula by their coordinated counterparts, and replacing [tex]m[/tex] by the slope that is given to you.
Let's assume the coordinates you are given are [tex](5,10)[/tex], and the slope you are given is 1.
By substituting into the general formula...
[tex]y=mx+c\\(10)=(1)(5)+c\\10=5+c\\10-5=c\\c=5[/tex]
...we can see that it is possible to find the y-intercept ([tex]c[/tex]).
Knowing the y-intercept, it is possible to plot the line and solve any question.
I'll leave a picture of the example used above when graphed.
